Where did it go wrong for Vettel?

This looked to be the year when they would finally maintain a championship fight with Mercedes; the season where the famous Scuderia could finally end their remarkable, decade-long title drought.

But just like 2017, their challenge has faded after the summer break, before spectacularly collapsing at the Japanese GP.

All is not yet lost, but, following their Suzuka success, Mercedes and Lewis Hamilton already have one hand on another championship double again.

How did this happen?Ferrari were in control of both championships less than three months ago, on a high after making huge strides with their car and engine over the triple header.

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Even as recently as a Belgian GP which Sebastian Vettel dominated, it was still clear that Ferrari held a significant car advantage.

But in the year's pivotal points, Ferrari faltered while Mercedes and Hamilton surged ahead. In Italy, a strategic mistake in qualifying was followed by a mistake by Vettel. In Singapore, where Ferrari were favourites to prosper, a qualifying lap of sheer brilliance was the critical difference.

Could Ferrari hit back in the Russia-Japan double header? They couldn't. While Mercedes pushed forward with a car that looks to be all-conquering on every track layout, Ferrari abandoned new parts in Japan after an unimpressive Sochi debut - a startling admission of failure in a crucial development race.

"Last year they lost it through reliability and their speed dipped as well," said Sky F1's Paul di Resta.

"When developments had to ramp up this year and they had to bring the real goodies for the last upgrade - it's not worked. Mercedes have just selected another gear and they're off."

It has left Ferrari the best part of half a second behind Mercedes over one lap, and leaves the championship in a position that was unimaginable just weeks ago.

Hamilton can claim the title with victory at the US GP, while Vettel is actually one point worse off in the standings than he was at this time last year.

Drivers making the differenceJust as Mercedes aren't the sole reason for Hamilton's incredible run of form, Ferrari aren't completely responsible for Vettel's downfall.

"For a four-time world champion, there's been too many mistakes," observed Di Resta.

The list is indeed long. Last year, Vettel shunted into Hamilton under the Safety Car in Azerbaijan, crashed out at the start of Singapore and tangled with the Mercedes and Verstappen in Mexico.

This year, he dropped from second to fourth by locking up in Baku, lost 15 points to Hamilton by clashing with Bottas in France, crashed out of the lead in Germany, lost out in combat with Hamilton at Monza, and made costly errors in qualifying and the race this weekend.

Vettel wasn't helped by Ferrari's incorrect tyre call at the start a wet-dry Japan qualifying that led to him chasing track time as well as pace-setter Hamilton - but as Sky F1's Anthony Davidson pointed out:

"Hamilton had the same conditions. Sebastian made multiple mistakes on that lap."

Vettel had moved up to fourth after a storming start from ninth on the grid, and would have been within striking distance of Mercedes if only he had bided his time to overtake a clearly slower Red Bull.

The fact that Max Verstappen was already facing a five-second penalty added to the perplexity of Vettel's decision to attempt a move up the inside of the Spoon corner, which immediately preceeded a long Suzuka straight.

"When you're in a world championship fight, can you afford to do something like that?" mused Di Resta. "I don't think you can."

It's hard to recall Hamilton making a significant error in the last two years, let alone the last four races. The Englishman has barely put a wheel out of line since the summer break, and is enjoying one of the purple patches of his career.

That can't be said about Vettel.

The long wait goes onIf not now, then when?

Ferrari have been more competitive in the past two years than in any of the seasons since their last drivers' title in 2008, but look certain to come up empty handed.

Unfortunately for them, they have come against a team which Hamilton describes as the "best in the world", and quite feasibly the most consistently dominant in F1.

They will, of course, go again next year - but even if they storm out of the blocks to get ahead of Mercedes, there won't be too many who would back this team, and this regime, to finish the job.

"I sense a deflating in the spirit of this team," noted Sky F1's Ted Kravitz in his notebook.

When will see Ferrari, the most successful team in the sport's history, return to the top?

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